IIRC, a diamante engine uses different cams that are tuned differently (less torque iirc) plus the dipstick may be on the wrong side. Others here can confirm that since I've only read about this swap.

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
Old web page
Old web page